EP0050681B1 - Elektrode für Schmelzflusselektrolyse - Google Patents

Elektrode für Schmelzflusselektrolyse Download PDF

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Publication number
EP0050681B1
EP0050681B1 EP80106580A EP80106580A EP0050681B1 EP 0050681 B1 EP0050681 B1 EP 0050681B1 EP 80106580 A EP80106580 A EP 80106580A EP 80106580 A EP80106580 A EP 80106580A EP 0050681 B1 EP0050681 B1 EP 0050681B1
Authority
EP
European Patent Office
Prior art keywords
electrode according
insulating
electrode
upper section
formed part
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP80106580A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0050681A1 (de
Inventor
Konrad Dipl.Ing. Koziol
Malcolm F. Dr. Dipl.Chem. Pilbrow
Christine M. Dr. Dipl.Chem. Zöllner geb. Möller
Dieter H. Dr. Dipl.Chem. Zöllner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
C Conradty Nuernberg GmbH and Co KG
Original Assignee
C Conradty Nuernberg GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by C Conradty Nuernberg GmbH and Co KG filed Critical C Conradty Nuernberg GmbH and Co KG
Priority to AT80106580T priority Critical patent/ATE15503T1/de
Priority to DE8080106580T priority patent/DE3071075D1/de
Priority to EP80106580A priority patent/EP0050681B1/de
Priority to US06/285,560 priority patent/US4462887A/en
Priority to CA000383638A priority patent/CA1181792A/en
Priority to JP56130375A priority patent/JPS5773196A/ja
Priority to CS817842A priority patent/CS249116B2/cs
Priority to HU813133A priority patent/HU188704B/hu
Priority to NO813604A priority patent/NO155105C/no
Priority to ES507053A priority patent/ES507053A0/es
Publication of EP0050681A1 publication Critical patent/EP0050681A1/de
Application granted granted Critical
Publication of EP0050681B1 publication Critical patent/EP0050681B1/de
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/02—Electrodes; Connections thereof
    • C25C7/025—Electrodes; Connections thereof used in cells for the electrolysis of melts
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
    • C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
    • C25C3/08—Cell construction, e.g. bottoms, walls, cathodes
    • C25C3/12—Anodes

Definitions

  • the invention relates to an electrode for melt flow electrolysis, in particular for the electrolytic production of metals such as aluminum, magnesium, sodium, lithium or compounds thereof, with an upper section made of metal (alloy), which includes a cooling device, the upper section being at least partially a high temperature resistant insulating coating is protected, and at least a lower section made of active material.
  • metal alloy
  • a number of ceramic materials e.g. B. according to GB-B 1 152 124 (stabilized zirconium oxide), US-B 4 057 480 (essentially tin oxide), DE-A 2 757 898 (essentially silicon carbide valve metal boride carbon), or according to DE-A 2 446 314 (ceramic base material coated with spinel compounds).
  • GB-B 1 152 124 stabilized zirconium oxide
  • US-B 4 057 480 essentially tin oxide
  • DE-A 2 757 898 essentially silicon carbide valve metal boride carbon
  • DE-A 2 446 314 ceramic base material coated with spinel compounds
  • a disadvantage of the use of electrodes which are formed from ceramic materials is - even after adding conductivity-increasing components - their often only moderate to medium electrical conductivity. This is only acceptable in processes where the electrode dimensions are small and the current path is short.
  • the electrodes for melt flow electrolysis e.g. B. of aluminum
  • the electrodes for aluminum production can be dimensioned up to 2250 x 950 x 750 mm, while typical graphite electrodes for magnesium production are 1700 x 200 x 100 or 0400 x 2200 mm, depending on the type of process.
  • the production of such solid blocks from the ceramic materials mentioned is expensive and results in considerable difficulties with regard to resistance to temperature changes and electrical internal resistance. In recent times, however, the efforts of the power-consuming industries have been directed particularly towards reducing the specific energy consumption, which is why ceramic solid electrodes have not found their way into practice here either.
  • the invention has for its object to provide an electrode for melt flow electrolysis, in which the disadvantages of the prior art described above are reduced.
  • This type of electrode should preferably be used as an anode.
  • an electrode of the type mentioned at the outset which is characterized in that a releasably attached molded part is provided as the insulating coating, which comprises a series of pipe sections, segments or half-shells which extend from the lower region of the upper section to or surrounded in the vicinity of a screw nipple that connects the upper section and the lower section.
  • a coolant such as B. liquids such as water or gases, e.g. B. air.
  • Electrodes of the type mentioned at the beginning have been proposed for use in the production of electric beams in electric furnaces in which an arc is emitted from the tip of the electrode. Due to the existence of the arc and its possibility of migration, the resulting extreme temperatures in the vicinity of the arc, but also due to the atmosphere in the electric steel furnace and the type of electrode operation, there are such serious deviations from the melt flow electrolysis that it is possible to use such types of electrodes for the implementation was not considered by melt flow electrolysis. With regard to such prior art, reference is made only by way of example to GB-B-1 223162, DE-B-2430817 or EP-A 12 573. These documents describe the electrodes there with regard to the specific requirements of the arc electrode and the efforts made to meet the specific requirements of the electrical steel production process.
  • a molded part is provided as an insulating coating in the electrode according to the invention, which is releasably attached.
  • the term “insulating” is to be understood as meaning an inert and shielding material from the electrolysis medium, which material may also be electrically insulating.
  • the electrode or anode according to the invention it is particularly advantageous if at least the area of the molded part that can come into contact with the electrolyte and the resulting products shields the metal shaft and possibly other metallic parts, in particular the nipple, in a gas-tight and liquid-tight manner .
  • the high-temperature-resistant, insulating molded part represents a series of pipe sections, segments, half-shells or the like, which surround the lower area of the upper section of the electrode up to the area of the screw nipple, possibly beyond.
  • the material of the insulating molding can, for. B. consist of high temperature resistant ceramic, but also z. B. represent graphite, which is applied with an insulating coating.
  • Such insulating, high-temperature resistant ceramic or other materials are known.
  • the insulating molded part is arranged between a lower partial area of the upper section made of metal and the lower, consuming section such that the outer edges of the molded part running in the direction of the electrode axis and those of the outer area of the upper section made of metal are essentially flush with each other.
  • the counter bearing on which the molded part is carried there are no restrictions with regard to the counter bearing on which the molded part is carried.
  • This can be a counterpart, likewise made of insulating material that can be subjected to high temperatures, the screw nipple itself, possibly even part of the active part itself, or a combination thereof.
  • the insulating molded part will not rest on the active part alone, provided that this is a consumable material, but will be at least partially carried by a non-"consumable", heat-resistant material.
  • the position of the molded part can of course be controlled in a suitable form during the manufacture of the electrode.
  • the insulating molded part can also during operation of the electrode, without the electrode having to be led out of the electrolysis furnace, through bores provided in the upper section through pins, threaded screws, etc. on the counter bearing, e.g. B. by the additional provision of springs.
  • the insulating molded part can be placed on holders, which can preferably be attached to the metal of the inner cooling unit.
  • holders which can preferably be attached to the metal of the inner cooling unit.
  • this is primarily taken into consideration in such applications of the electrodes, where it depends on the free mobility or the "moving up" more intact (insulating or electrically conductive) tender) individual segments in case of damage to a lower segment does not arrive.
  • the insulating molded part does not comprise the entire area of the metal shaft to be protected, but instead in an area where less stress can be expected, instead of the further molded part, an insulating, highly fire-resistant injection molding compound anchored with holding pieces is used.
  • Such insulating molding compounds are known per se, which with holding pieces, the z. B. soldered, can be attached.
  • Amorphous carbon, graphite, ceramic conductors or a composite of inorganic fibers with an electrochemically active material can be listed as examples of active materials which are connected to the upper section by one or more screw nipples or threads.
  • active materials which are connected to the upper section by one or more screw nipples or threads.
  • EP-A 22 921 where particularly preferred composites composed of inorganic fibers with an electrochemically active material are listed.
  • the description of the active materials in this regard, as well as their arrangement, is to be regarded as fully introduced into the present application by express reference to this European patent application. It is explained in detail there that the active material can be formed from a number of rods, plates, tubes or the like, which are connected or separated from one another.
  • the lower section may consist of active material in several units, which are held by one or more nipple connections, it being possible for the units to be arranged next to one another and / or among one another. So especially with regard to consumable active ingredients, eg. B. graphite, intermediate pieces of such material are considered, to which a completely consuming unit can in turn be screwed. As a result, the last active unit can be completely used up without the nipple connection to which the metallic upper section is connected being exposed to a hazard.
  • consumable active ingredients eg. B. graphite
  • the electrode according to the invention has a number of advantages: the extremely low current and voltage losses on the way to the active part of the electrode should be emphasized. As a result, considerable energy savings can be achieved compared to conventional solid blocks, whether made of carbon, graphite or ceramic material. Furthermore, the side burn-off is minimized, since it is no longer the entire electrode but only its active part that is exposed to the aggressive electrolysis medium and the reaction gases and vapors that develop in the process. Finally, the electrode can be used in a variety of ways, since its construction allows the use of a spectrum of active materials which can be used in principle in the field of melt flow electrolysis.
  • the insulating molded part can also be easily inserted in a targeted position during manufacture.
  • the mechanical strength can be improved by using an insulating, external solid part.
  • the tongue and groove system provides, for example, complete and comprehensive protection of the sensitive metal area of the electrode. If the lower area of the "protective shield" of the electrode is nevertheless damaged, it can usually continue to work for as long as it is necessary to replace the consumable part made of graphite, for example. When the electrode is removed, the corresponding replacement of the damaged individual segment, etc. can then easily be carried out.
  • the cooling medium for. B. water, air or inert gas
  • the cooling medium also enters a chamber within the screw nipple 1, the z. B. is formed from cast iron, nickel or a temperature-resistant, corrosion-resistant metal alloy.
  • the upper section 5 made of metal consists of an upper area of larger diameter and a lower-lying area of smaller diameter, which is drawn into the screw nipple 1, which connects to the lower section 6 from z. B. consumable material, e.g. B. graphite or ceramic active material.
  • the insulating molding 4 is by a counter bearing 7, for. B. made of high temperature resistant, insulating ceramic. In the upper region, the insulating molded part 4 is delimited by the upper edge of the region of the larger diameter of the metal shaft.
  • the insulating molded part 4 is divided into segments which are slidable in the direction of the electrode axis when a (lower) segment breaks out. Alternatively, they can also be held by hook elements 14.
  • additional bores 8 can be provided, through which the inserted pins 9 and the spring 10 ensure a good fit of the insulating molded part 4. From Fig. 2 as well as Fig. 4, the use of half shells in the composite or of rings, z. B. from graphite coated with an insulating coating.
  • the lower section 6 made of consumable or durable material is divided into a series of individual rods 20 which are bound by the nipple 1.
  • the preferred lateral power supply takes place via jaws 18, advantageously made of graphite, which are fastened, not shown, to holders, preferably on the metal shaft.
  • jaws 18 advantageously made of graphite, which are fastened, not shown, to holders, preferably on the metal shaft.
  • Fig. 1 the alternative possibility of attaching the jaws 18 to the power supply rail itself is shown.
  • Gas purging channels which are not shown in the figures, can be provided between the insulating layer 4 and the upper section 5.
  • the gas flushing can damage the insulating ceramic, z. B. over a corresponding pressure drop, can be easily determined.
  • a certain cooling effect is possible.
  • the upper section 5 and / or the nipple connection 1 or the outer surfaces thereof can be coated with a heavy-duty coating (12).
  • this coating can be designed to be electrically conductive or also insulating.
  • the coating can also consist of a high-temperature-resistant, conductive material, in which case this material has the effect of a “heat shield” or “inert shield” to protect the underlying metal.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
EP80106580A 1980-10-27 1980-10-27 Elektrode für Schmelzflusselektrolyse Expired EP0050681B1 (de)

Priority Applications (10)

Application Number Priority Date Filing Date Title
AT80106580T ATE15503T1 (de) 1980-10-27 1980-10-27 Elektrode fuer schmelzflusselektrolyse.
DE8080106580T DE3071075D1 (en) 1980-10-27 1980-10-27 Electrode for igneous electrolysis
EP80106580A EP0050681B1 (de) 1980-10-27 1980-10-27 Elektrode für Schmelzflusselektrolyse
US06/285,560 US4462887A (en) 1980-10-27 1981-07-21 Apparatus for fusion electrolysis and electrode therefor
CA000383638A CA1181792A (en) 1980-10-27 1981-08-11 Apparatus for fusion electrolysis and electrode therefor
JP56130375A JPS5773196A (en) 1980-10-27 1981-08-21 Electrode for electrolytic refining of molten substance
CS817842A CS249116B2 (en) 1980-10-27 1981-10-26 Electrode for fused-salt electrolysis
HU813133A HU188704B (en) 1980-10-27 1981-10-26 Electrode for melted salt-electrolysis
NO813604A NO155105C (no) 1980-10-27 1981-10-26 Elektrode for smelteelektrolyse.
ES507053A ES507053A0 (es) 1980-10-27 1981-10-26 Perfeccionamientos en los electrodos para electrolisis de metales.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP80106580A EP0050681B1 (de) 1980-10-27 1980-10-27 Elektrode für Schmelzflusselektrolyse

Publications (2)

Publication Number Publication Date
EP0050681A1 EP0050681A1 (de) 1982-05-05
EP0050681B1 true EP0050681B1 (de) 1985-09-11

Family

ID=8186859

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80106580A Expired EP0050681B1 (de) 1980-10-27 1980-10-27 Elektrode für Schmelzflusselektrolyse

Country Status (10)

Country Link
US (1) US4462887A (cs)
EP (1) EP0050681B1 (cs)
JP (1) JPS5773196A (cs)
AT (1) ATE15503T1 (cs)
CA (1) CA1181792A (cs)
CS (1) CS249116B2 (cs)
DE (1) DE3071075D1 (cs)
ES (1) ES507053A0 (cs)
HU (1) HU188704B (cs)
NO (1) NO155105C (cs)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3135912A1 (de) * 1981-09-10 1983-03-24 C. Conradty Nürnberg GmbH & Co KG, 8505 Röthenbach Axial verschiebbarer elektrodenhalter zum einsatz bei der schmelzflusselektrolyse
DE3215537A1 (de) * 1982-04-26 1983-10-27 C. Conradty Nürnberg GmbH & Co KG, 8505 Röthenbach Verwendung von temperatur- und korosionsbestaendigen gasdichten materialien als schutzueberzug fuer den metallteil von kombinationselektroden fuer die schmelzflusselektrolyse zur gewinnung von metallen, sowie hieraus gebildete schutzringe
US4477911A (en) * 1982-12-02 1984-10-16 Westinghouse Electric Corp. Integral heat pipe-electrode
DE3537575A1 (de) * 1985-10-22 1987-04-23 Conradty Nuernberg Inerte verbundelektrode, insbesondere anode fuer die schmelzflusselektrolyse
DE3838828A1 (de) * 1988-11-17 1990-05-23 Vaw Ver Aluminium Werke Ag Kohleelektrode mit gasdichter, temperaturbestaendiger schutzglocke
NO176885C (no) * 1992-04-07 1995-06-14 Kvaerner Eng Anvendelse av rent karbon i form av karbonpartikler som anodemateriale til aluminiumfremstilling
NO337977B1 (no) * 2008-10-31 2016-07-18 Norsk Hydro As Fremgangsmåte og anordning for ekstrahering av varme fra aluminium elektrolyseceller
JP5787580B2 (ja) * 2011-04-06 2015-09-30 株式会社東芝 電解還元装置
CN102560552A (zh) * 2012-01-04 2012-07-11 饶云福 一种应用于电解铝阳极钢爪修复中的助熔剂

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0012573A1 (en) * 1978-12-19 1980-06-25 British Steel Corporation Electric arc furnace electrodes

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3385987A (en) * 1966-10-24 1968-05-28 Westinghouse Electric Corp Electrode for an arc furnace having a fluid cooled arcing surface and a continuouslymoving arc thereon
CH575014A5 (cs) * 1973-05-25 1976-04-30 Alusuisse
CH592163A5 (cs) * 1973-10-16 1977-10-14 Alusuisse
DE2725537A1 (de) * 1977-06-06 1978-12-14 Korf Stahl Elektrode fuer lichtbogenoefen
US4145564A (en) * 1978-01-30 1979-03-20 Andrew Dennie J Non-consumable electrode with replaceable graphite tip

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0012573A1 (en) * 1978-12-19 1980-06-25 British Steel Corporation Electric arc furnace electrodes

Also Published As

Publication number Publication date
CS249116B2 (en) 1987-03-12
ES8207593A1 (es) 1982-10-01
NO155105C (no) 1987-02-11
NO813604L (no) 1982-04-28
NO155105B (no) 1986-11-03
HU188704B (en) 1986-05-28
JPS5773196A (en) 1982-05-07
EP0050681A1 (de) 1982-05-05
DE3071075D1 (en) 1985-10-17
CA1181792A (en) 1985-01-29
US4462887A (en) 1984-07-31
ES507053A0 (es) 1982-10-01
ATE15503T1 (de) 1985-09-15

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